[PATCH] btrfs: Fix 64-bit divisions in btrfs_commit_stats_show() on 32-bit

[PATCH] btrfs: Fix 64-bit divisions in btrfs_commit_stats_show() on 32-bit

[Geert Uytterhoeven]

On 32-bit (e.g. m68k):

    ERROR: modpost: "__udivdi3" [fs/btrfs/btrfs.ko] undefined!

Fix this by using div_u64() instead.

Reported-by: noreply@ellerman.id.au
Fixes: e665ec2ab6e1ae36 ("btrfs: Expose the BTRFS commit stats through sysfs")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
---
 fs/btrfs/sysfs.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index bce2573b02861149..a24cf7e0900a23cb 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -9,6 +9,7 @@
 #include <linux/spinlock.h>
 #include <linux/completion.h>
 #include <linux/bug.h>
+#include <linux/math64.h>
 #include <crypto/hash.h>
 
 #include "ctree.h"
@@ -1002,9 +1003,9 @@ static ssize_t btrfs_commit_stats_show(struct kobject *kobj,
 		"max_commit_ms %llu\n"
 		"total_commit_ms %llu\n",
 		fs_info->commit_stats.commit_count,
-		fs_info->commit_stats.last_commit_dur / NSEC_PER_MSEC,
-		fs_info->commit_stats.max_commit_dur / NSEC_PER_MSEC,
-		fs_info->commit_stats.total_commit_dur / NSEC_PER_MSEC);
+		div_u64(fs_info->commit_stats.last_commit_dur, NSEC_PER_MSEC),
+		div_u64(fs_info->commit_stats.max_commit_dur, NSEC_PER_MSEC),
+		div_u64(fs_info->commit_stats.total_commit_dur, NSEC_PER_MSEC));
 }
 
 static ssize_t btrfs_commit_stats_store(struct kobject *kobj,
-- 
2.25.1

Re: [PATCH] btrfs: Fix 64-bit divisions in btrfs_commit_stats_show() on 32-bit

[David Sterba]

On Thu, Jun 16, 2022 at 10:08:14AM +0200, Geert Uytterhoeven wrote:
> On 32-bit (e.g. m68k):
> 
>     ERROR: modpost: "__udivdi3" [fs/btrfs/btrfs.ko] undefined!
> 
> Fix this by using div_u64() instead.
> 
> Reported-by: noreply@ellerman.id.au
> Fixes: e665ec2ab6e1ae36 ("btrfs: Expose the BTRFS commit stats through sysfs")
> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

Folded to the patch, thanks.